The present invention concerns novel derivatives of thiadiazole compounds and their use as functional additives for lubricating compositions and alcohol fuel. More particularly the novel thiadiazoles are derived from 2,5-dimercapto-1,3,4-thiadiazole and succinic acid or anhydride.
Lubricants which are used for heavy duty service such as maintenance of diesel engines, internal combustion engines and the like contain a variety of additives to prevent their deterioration during use and to improve the overall performance of the lubricant. These additives can cause excessive wear of special components of the engine due to chemical reactions between the additive and the metal. Particularly detrimental are sulfur-containing additives which are widely used as antioxidants and antiwear agents. The sulfur compounds tend to corrode those metal parts which contain copper, bronze, silver and other sulfur-reactive metals.
It has been now discovered that certain succinate derivatives of 1,3,4-thiadiazole function as antioxidants and antiwear agents as well as corrosion inhibitors when used in lubricating compositions. Furthermore, the novel succinate derivatives display corrosion inhibition and antiwear functionality in alcohol fuel. It is desirable to add such additives to alcohol fuel to control corrosion and ring bore wear.